Batteries (and sometimes multiple batteries) are used to power various types of systems. For example, batteries are used to power electric vehicles or hybrid electric vehicles. The batteries in these systems can be configured as packs of batteries that provide voltages in the 150-600 volt range.
However, the accessories that are used in the same vehicles typically require voltages that are much less than 150-600 volts. As such, the vehicle must have a conversion apparatus or circuit that reduces the battery voltage to an acceptable level. One such conversion system that can be used is a DC-DC converter. In some examples, the DC-DC converter reduces the voltage from the 150-600 volt range to a 12 volt value (or less).
Although DC-DC converters have been used, they typically have operational issues and limitations. For instance, the conversion circuitry in the DC-DC converter typically utilizes transistors. Transistors can be damaged or destroyed when too high a voltage is applied. Some previous approaches have relied exclusively on resistors capacitors and diodes to limit the voltages that can be applied to the transistors. However, this approach wastes energy that can be used in the system as excess energy and voltage is simply burned away by the resistor. Electric or hybrid vehicles need to conserve as much energy as possible and wasted energy runs counter to this goal.
In summary, previous attempts at overcoming these problems have not generally been successful. These previous systems and approaches had resulted in poor energy conversion efficiency ultimately resulting in user dissatisfaction or lack of consumer interest.
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